System for providing a product package with a carrying handle

ABSTRACT

This invention relates to a system for the automated attachment of a carrying handle on product packages. The system incorporates devices for advancing the products, means for the forward-feeding of a foil-strip designed to serve as a carrying handle, as well as at least one rotating element, whereby the foil strip is guided over the rotating element in such fashion that a rotation of the rotating element causes each one end of the foil strip to be attached to opposite sides of the product package. According to the invention, the system employs at least one rotating element featuring at least three arms. Thus, in advantageous fashion, the throughput rate is augmented, and the length of the carrying handle is determined by the cove formed between each two arms of the rotating element.

FIELD OF THE INVENTION

[0001] This invention relates to a system that provides a product package with a carrying handle.

DESCRIPTION OF THE RELATED ART

[0002] Product package systems include, as a minimum, means for advancing the product, means for the forward-feeding of a foil strip designed to serve as a carrying handle, as well as one or several rotating elements. The foil strip is guided across the rotating elements in such fashion that, as the rotating elements turn, one end each of the foil strip is attached to opposite sides of the product, forming a carrying handle on the product package.

[0003] The product package to be so equipped includes, in particular, merchandise packaged in plastic or cardboard, such as beverage bottles or canned goods as well as other items that come in multiple units. These multi-unit packs are provided with a carrying handle for easier handling and transporting. The product, whether individually or in groups such as six-packs, is surrounded by outer packaging to which a strip of foil, usually consisting of a plastic material, is attached as a carrying handle. Items thus equipped with a carrying handle are mass products and, accordingly, there is a need for the automated attachment of these carrying handles to be as simple, trouble-free and throughput-intensive as possible.

[0004] The prior art already employs this general type of automated attachment of carrying handles to product items. In the process involved, a typically self-adhesive foil strip is placed across a rotating plate in such fashion that each one end of the foil strip is attached to opposite sides of a prepackaged product that is positioned on a conveyor underneath the rotating plate. Specifically, the plate is initially in a vertical position and the adhesive side of the foil strip faces the product to be provided with a handle. The product, as it travels on the conveyor, strikes the adhesive end of the foil strip, thus attaching it to the product packaging. The plate then tilts into a horizontal position. The product is advanced on the conveyor by a distance that corresponds to its width, whereby a length of the foil strip is dispensed that is sufficiently long to form the carrying handle. Thereupon the plate is again tilted 90° into a vertical position in the process of which the other end of the foil strip is attached on the product package on the side opposite the first end. By means of suitable cutting devices such as a cleaver the foil strip is cut either before or after the second end of the handle is attached to the product package.

[0005] Prior-art systems of this type have been described for instance in EP 0560 699 and in U.S. Pat. No. 6,234,230. The systems according to these publications operate by the same principle as discussed above and differ from each other primarily by the configuration of the cutting device that cuts the foil strip so as to form the finished handle. Those systems each have a plate as the rotating element. However, using a plate has its drawbacks. To ensure the proper length of the carrying handle to be formed, the product must be precisely positioned on the conveyor while the forward movement of the product on the conveyor and the corresponding movement of the plate from the horizontal into the vertical position must be perfectly synchronized, otherwise the handle would end up being too short. The prior art also describes retaining elements mounted on the plate, which serve to hold the foil strip on the plate, usually centered, so that the movement of the plate reels off an adequate length of the foil strip for forming the handle. The synchronism, required when using a plate, in terms of the rotation of the plate and the feed rate of the product, is difficult to maintain and can lead to problems. For example, the carrying handle may not be long enough, resulting in too small an opening for convenient carrying with one hand. To avoid that problem, prior-art systems typically feature sensors or other means for determining the position and thus the length of the foil strip. Moreover, the need for precise synchronism makes it impossible to obtain the necessary high throughput rates. Synchronized settings of this type also require periodic checking which is relatively costly in terms of time and money.

SUMMARY OF THE INVENTION

[0006] The invention provides improvements to product packaging systems that are designed to increase their throughput and render the attachment of carrying handles less error-prone.

[0007] More specifically, the system incorporates at least one rotating element with at least three arms.

[0008] Moreover, the system also eliminates a plate-shaped element that is present in prior art designs. For example, a system with at least three arms significantly increases throughput since within a particular timeframe multiple arms can attach carrying handles to a larger number of products. Of course, within the scope of this invention it is possible to use more than three arms. In each case these arms are positioned around a rotating element.

[0009] The particular advantage of the system lies in the fact that a multi-arm rotating element rather elegantly overcomes the difficulty of obtaining the right strip length for producing an easy-to-grasp carrying handle. As indicated above, the problem with prior-art designs is that, when using a plate that has solid planar sides, it is not possible to attach the foil strip on the opposite side simply by rotating the plate. Instead, it is necessary first to fasten the foil strip typically near the axis of rotation so as to be able to unreel a sufficiently long piece of foil-strip material for instance off a dispensing reel, for forming a grasping space above the package. In most cases, this requires an extremely precise setting of the forward feed of the products on the conveyor.

[0010] This problem is circumvented by the use, according to this invention, of a multi-arm rotating element. Each of the minimum of three arms of the rotating element per this invention extends at a specific, predefined angle. Thus, a certain inward curvature, or cove, is created between the arms of the rotating element along whose contour the foil strip can be guided as provided for by this invention. The automatic result is a foil-strip section of a particular length as specified for the carrying handle to be produced, which length varies as a function of the selected length of the arms of the rotating element. It follows that, according to the invention, this section that is to become a handle is formed independent of the position or feed rate of the product package. This obviates the undesirable need, common in prior art, for the plate-shaped paddle in interaction with the package, to dispense and guide the foil strip. The cove defined by the angular spacing and the length of the arms makes it possible, totally independent of the packaging, to precut handle sections of a particular length to be used and, after the precutting process, to bring the handle up to the package. The drawback of an interdependence of the formation of a carrying handle and the package is eliminated. Guiding the foil strip along the inward curvature, or cove, as provided for by the invention, defines both the length and the arch of the carrying handle, creating in each case a convenient-to-grasp handle opening. As a result of the use of a rotating element with at least three arms per this invention, susceptibility to problems can be reduced and throughput increased.

[0011] The carrying handle is preferably produced from a self-adhesive foil strip. Particular preference is given to a prefabricated foil strip that includes on one side of the strip a neutral, i.e. nonadhesive section surrounded on the outside by two self-adhesive sections. In advantageous fashion this ready-to-attach foil-strip material is in the form of rolls with foil-strip lengths of 5,000 to 15,000 meters, the advantage being that the foil-strip dispenser needs to be refilled less often which in turn benefits the maintenance-free operating time of the system. It is also possible to use nonadhesive foil strips in conjunction with this invention. Foil strips of that nature may be attached to the product package by a separate gluing, stapling or similar operation. In that case the system, and preferably its arms, should incorporate the provisions necessary for fastening the strip to the rotating element.

[0012] In an exemplary design implementation, the angular distance between the arms mounted on the rotor of the rotating element is uniform. The advantage of this is that, if the length of the arms is also identical, handle sections of always the same size are produced in the cove between two arms. It follows that the carrying handles can be produced to be consistently of the same length without deviation. Time-consuming inspections are unnecessary, the length of the handle is predefined and essentially uniform.

[0013] In an exemplary design enhancement, the system per this invention includes means for adapting the foil strip to the angular geometry between the arms of the rotating element. Such adaptation may be accomplished for instance by means of a vacuum which causes the foil strip to hug the cove between the arms. Electrostatic conformation to the contour is also possible.

[0014] In an exemplary design version, the adaptation of the foil strip to the inward curvature between the arms is assisted by a counter element that adapts the shape of the foil strip to the angular geometry between the arms of the rotating element. The counter element preferably brings this about by exerting a certain amount of pressure on the foil strip, causing a sufficient length of foil-strip material to be pulled off a foil-strip dispenser such as a reel and guiding the foil strip along the contour of the cove rather than stretching it between the arms.

[0015] In an exemplary design enhancement, the counter element is in the form of another rotating element with the same number of arms as the rotating element that carries the foil strip. The arms of the second rotating element push the foil-strip material into the coves between the arms of the first rotating element.

[0016] In advantageous fashion, the rotating element that serves as a counter element and the rotating element carrying the foil strip rotate synchronously in opposite directions. As a result, the arm of the second rotating element that functions as the counter element automatically reaches into the middle between two arms of the rotating foil-strip-carrying element, thus pushing the foil strip into the cove. The drive mechanism driving the rotating foil-strip-carrying element is preferably coupled with the second rotating element that provides the counter action. This will automatically synchronize the mutually opposite rotation of the rotating elements, preventing misalignment in advantageous fashion.

[0017] The system according to this invention is advantageously equipped with at least one cutting device for cutting the foil strip. The cutting devices may be designed in essentially conventional fashion for instance so as to be extensible from the associated arm of the rotating element. However, a particular advantage is offered by a design employing a cutting device in the form of a fixed blade that serves to cut the foil strip carried by the rotating element. Accordingly, in a preferred design version the cutting device is installed in a fixed position. The rotating element carrying the foil strip and the cutting device are so positioned relative to each other that the foil strip carried by the rotating element is cut as the rotating element passes the stationary cutting device. The momentum of the rotary movement causes the foil strip to be severed by the cutting blade.

[0018] In conjunction with a stationary cutting device it is particularly advantageous if the ends of the arms of the rotating element carrying the foil strip are equipped, suitably spaced from the arms, with guides through which passes the foil strip. The guide may for instance be in the form of a roller that is preferably connected, laterally with only one end, to the tip of the respective arm of the rotating element. This creates a gap between the guide and the end of the arm of the rotating element in which gap the blade of the cutting device can engage during the rotation, allowing the foil strip to be severed without difficulty.

[0019] In an advantageous design enhancement, the length of the arms of the rotating element is adjustable. For example, they may be extended telescope-style. This is easily feasible with a rotating element per this invention and offers the advantage of permitting a length variation of the precut carrying handle between the arms in adaptation to other product sizes.

[0020] The rotating element consists essentially of a rotor with arms attached to it. In another advantageous design variation, the arms are removable. This offers the advantage of permitting the replacement of individual arms for instance in the event of damage without requiring a replacement of the entire rotating-element assembly. This constitutes another significant advantage over the prior-art plate that must be replaced when damaged. It also provides the possibility to mount arms of different lengths for instance when telescopic extensibility is not being considered. This advantageous design enhancement makes the system per the invention extremely versatile. This feature also allows the mounting of arms designed for the fastening of nonadhesive foil strips and incorporating corresponding, special provisions for the attachment of nonadhesive foil strips on the product concerned. Overall, these capabilities significantly expand the flexibility of the system.

[0021] In another advantageous design enhancement, the arms are mounted on a rotor whose circumference can be increased. This makes it possible in advantageous fashion to vary the distance, i.e. the angular spacing, between the arms, thus providing additional adaptation capabilities for diverse types of packaging and a range of package sizes. It also provides the possibility to mount a larger number of arms on the rotor. These are preferably inserted in appropriately provided slots in the rotor and then locked in place.

[0022] In an advantageous design version of this invention, the rotation of the rotating element is torque-controlled. In this case the rotating element is set in motion the moment a product is advanced and touches an arm at an angle that is a function of the number of arms on the rotor, which in the case of a three-arm rotating element is 120°. In advantageous fashion, a torque-detecting servomotor, easily and precisely controllable, drives the rotating element. The torque-controlled rotation prevents the arms from impacting on the product and thus from damaging it. The torque controlling the rotation is preferably adjustable, which offers an advantage by permitting adaptation to light-weight or heavy products. Torque-controlled rotation of the rotor also makes it possible for the foil strip to be advanced by the feed system as a function of the rotation of the rotating element, meaning that the forward feed of the foil strip is essentially governed by the rotation of the rotating element. This is an advantageous way to eliminate complex adjustments for synchronizing these functions.

[0023] In another advantageous design version, the rotating element can be equipped with provisions for an at least temporary retention of the foil strip on the arms of the rotating element. This prevents in advantageous fashion any slippage of the foil strip separating it from the arms or from the contour of the coves between the arms of the rotating element.

BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Other details, features and advantages of this invention are explained in more detail in the following description of a design example with reference to the drawings. Referring to the exemplary drawings wherein like elements are numbered alike in the Figures:

[0025]FIGS. 1a to 1 e illustrate in diagrammatic form the operating principle of a system per this invention for the automated attachment of a carrying handle on product packages.

DETAILED DESCRIPTION

[0026] In a schematic illustration the FIGS. 1a to 1 e explain the mode of operation of the system according to this invention. Since these illustrations are merely intended to explain the basic operating principle, not all components of the system are shown, to the extent that they reflect prior art.

[0027]FIG. 1a shows how the prepackaged products 1 a to 1 c are transported, via a conveyor system such as a conveyor belt, not illustrated, in the feed direction F. The rotating element 3 has three arms 4 a to 4 c that guide the foil strip 5. The arms 4 are mounted on the rotor 11 at a uniform angle W relative to one another. This creates coves 15 between the arms 4. The foil strip 5 is dispensed off a reel, not shown, and guided via suitable foil-strip feed guides 6 to the rotating element 3. The foil strip 5 is unreeled by the rotary movement of the rotating element 3. The system also incorporates a cutting device 7. The cutting device consists of a blade 8, which is mounted in a stabilizing cylinder 9. A second rotating element 10 is positioned above the rotating foil-strip-carrying element 3.

[0028] In the situation depicted in FIG. 1a, the product 1 a has already been equipped with a carrying handle 2. The next step will be the attachment of a carrying handle on product 1 b. The arm 4 a of the rotating element 3 extends in a vertical position. For a better understanding, the arm 4 a. which in FIG. 1a extends in a vertical position, is shown with a darker outline in all figures, permitting facilitated tracking of its position during the attachment of a carrying handle on product 1 b. A loose end 12 of the foil strip 5 which is to become a carrying handle 2, is located next to the vertical arm 4 a. The section constituting that end 12 is self-adhesive, with the self-adhesive side facing the product 1 b. The product is transported, via the conveyor, not shown, in the feed direction F and strikes the vertical arm 4 a and thus the self-adhesive end 12 of the foil strip 5. As a result, the end 12 is attached to one side of the product package 1 b.

[0029]FIG. 1b now shows the rotary movement of the individual rotating elements. As indicated, the rotating element 3 carrying the foil strip 5 and the rotating element 10 serving as the counter element rotate in opposite directions. The rotating element 3 rotates in a counter-clockwise direction, the rotating counter element 10 turns in the clockwise direction. The arrows 13 and 14 show the respective directions of rotation. The counter-clockwise rotation of the rotating element 3 causes the foil strip for the carrying handle, extending along the cove between the arms 4 a and 4 b, to be guided over product 1 b. As will be evident, the rotary movement of the rotating element 3 took the foil strip 5 past the cutting device 7 where the blade 8 cut the foil strip 5, the result again being two self-adhesive ends 16 and 17. The cutting action takes place when one of the arms extends in a vertical direction.

[0030]FIG. 1c emphasizes the relative position between the rotating element 3 carrying the foil strip 5 and the rotating element 10 acting as the counter element. The rotating elements 3 and 10 are of identical dimensions and are so synchronized that each arm of a rotating element, when in a vertical position, points exactly at the center of the cove 15 between two arms 4 of the other rotating element. Since the arms 4 of the rotating elements 3 and 10 are identical in length, the vertically extending arm of one rotating element (in the example shown, arm 4 c of the rotating element 3) reaches into the gullet of the cove 15 of the other rotating element (in the example shown, rotating element 10), but does not have to touch it. In its position shown in FIG. 1c, the arm 4 d of the rotating counter element 10 extends in a direction essentially parallel to the foil strip 5, which is being pulled off the reel, not shown. As a result of this positioning, shown in FIG. 1d, the continued rotary movement of the two rotating elements 3 and 10 causes the arm 4 d of the rotating element 10 to press against the foil strip 5, thus helping to pull the latter out of the feed guide 6. This illustration also demonstrates the function of the rotating element 10 as a counter element in that its arm 4 d presses the foil strip 5 against the concave contour of the cove 15 between the arms 4 a and 4 c. As can also be seen in FIG. 1d, the rotary movement of the rotating element 3 causes the section of the foil strip 5 that is positioned in the cove between the arms 1 a and 1 b and constitutes the carrying handle, to be guided over the product 1 b to the side of product 1 c opposite the first end 12.

[0031]FIG. 1e shows the completion of an operating cycle of the system. In the position shown, the arm 4 b now extends in a vertical direction. It is in this position that the self-adhesive end 16 is attached to the product 1 b, thus completing a finished carrying handle 2 on product 1 b. The conveyor now advances the product packages until product 1c strikes the vertically extending arm 4 b of the rotating element 3, causing the end 17 of the foil strip 5 to be attached to the right side of product 1 c. At this point a new cycle can begin. As can be seen in FIG. 1e, the arm 4 d of the rotating element 10 is also in a vertical position, pointing at the center of the cove 15 between the arms 4 a and 4 c. This causes the foil strip 5 to hug the contour of the cove 15 after the pressure exerted by the arm 4 d has unreeled enough foil-strip material 5 to extend over the length of the contour of the cove 15, defining at this point the length of the next, essentially ready-to-attach carrying handle. The seating of the foil strip 5 in the cove 15 may be assisted for instance by a vacuum, by electrostatic attraction or by clamping devices to prevent the foil strip from slipping out of the cove. As described, the length of the carrying handle is determined in advantageous fashion altogether independent of any contact with the product, thus eliminating any alignment problems or errors. This ensures a handle opening 18 that will always be large enough to be grasped with one hand. 

1. A system for an automated attachment of carrying handles on product packages, the system comprising: devices for advancing products; means for dispensing a foil strip that is to serve as a carrying handle; and a first rotating element, the first rotating element includes at least three arms, wherein the foil strip is guided over the first rotating element in such fashion that a rotation of the first rotating element causes each one end of the foil strip to be attached to opposite sides of the product.
 2. The system as in claim 1, wherein the arms of the first rotating element are spaced apart by a uniform angular distance.
 3. The system as in claim 1, further comprising means for conforming the foil strip to an angular geometry between the arms of the first rotating element.
 4. The system as in claim 1, further comprising a counter element that adapts the foil strip to the angular geometry between the arms of the first rotating element.
 5. The system as in claim 4, wherein the counter element is a second rotating element having a same number of arms as the first rotating element.
 6. The system as in claim 5, wherein the second rotating element and the first rotating element rotate synchronously in opposite directions.
 7. The system as in claim 1, further comprising at least one cuffing device for cutting the foil strip.
 8. The system as in claim 7, wherein the at least one cutting device is mounted in a fixed position, wherein the first rotating element and the cutting device are positioned in relation to each other so that when the foil strip is guided over the first rotating element, the foil strip is severed when the rotation of the first rotating element moves past the cutting device.
 9. The system as in claim 1, further comprising a guide element that serves to guide the foil strip, wherein the foil strip is carried on the first rotating element at a tip of the arms.
 10. The system as in claim 1, wherein a length of the arms of the first rotating element is adjustable.
 11. The system as in claim 10, wherein the arms are extensible in a telescoping fashion.
 12. The system as in claim 1, wherein the arms are mounted on a rotor whose circumference is expandable.
 13. The system as in claim 12, wherein the arms are mounted on the rotor in removable fashion. 